Three core cable hot field distribution and coaxial heat road model feasibility study

10 kV three-core XLPE cables are widely used in network distribution and transmission. Their capacity will directly affect the reliable operation of the transmission line. Currently, the carrying capacity of 10 kV three-core cable is low and they often full load or overload operation. Therefore, its failure rate is much higher than the high-voltage single-core cable. It is necessary to study the three-core cable internal thermal field distribution and the feasibility of coaxial treatment of the three-core cable in modeling its thermal circuit. In this paper, use the finite element method to simulate the model of three-core cable. Found out the thermal field distribution of 10kV three-core cable, and verified it through the experimental data. Proved that there is a isothermal area in the middle of the cable which is enclosed by the three cores. It makes feasible for the coaxial treatment of the three-core cable and help to simplify the thermal circuit model of three-core cable.